Reposition the latest news in the admin dashboard

This way all that stuff doesn't get in the middle. We might need to think
of a better place to put it.
Random cleanups
Bugfix: Add missing import
Followup: Display only critical counts in stats tables

This is necessary because we still have non-critical checks, and we
decided to only highlight the counts for the critical ones.
Bugfix: Display critical checks count, not suggestions count